What is stereo?

There are now two system of high fidelity, monophonic (monaural) and stereophonic. Monophonic is a system that starts from one microphone and is fed through a single high fidelity set. Stereophonic is a double system. Two separate microphones are placed at different sides of the orchestra and two different systems are used to keep the two signals or channels separated. Two separate speakers are used, placed on different sides of you room. Stereo is much like 3-D photography, two slightly different sound reach your ears giving you a new dimension in sound.

H.H. Scott '59

Teac AS-M30

Stereo Integrated Amplifier

For years Teac has been justifiably recognized as a world leader in tape recording and playback equipment. Teac tape decks provide total performance, not only in reliable, high stability tape transport mechanisms, but also in ultra low distortion amplification circuitry.
This advanced signal processing technology has been fully incorporated in our new line of stereo integrated amplifiers. They offer great sound and versatility with plenty of useful (not excess) power, and important, functional features – not just fancy frills.
Teac amps really give you your money's worth.
 Designed for high performance and smooth power, the AS-M30 is perfect for the audio enthusist who knows and wants good sound. The kind ofmusic fan who doesn't feel the need for one of today's astronomically – priced amplifiers with needlessly high power output (and consumption).
The latest technology has been combined with an all-new look at circuit configuration and features, resulting in vastly improved reliability plus lower distortion over the entire frequency and power range.
The AS-M30 is a trend-setting answer to what an integrated amplifier should be.

All-Stage Direct-Coupled OCL Power Amplifier
The power amplifier section includes a differential input stage, assuring minimum noise and distortion throughout the entire power range, and an OCL (Output Capacitor-Less) output stage for improved low frequency response and damping. All stages are direct coupled, meaning that the signal path is free from waveform-distorting coupling components. This assures accurate signal transmission – from first stage to output.
 Low Noise Integrated Phono EQ Amplifier
A differential first stage with current mirror circuitry achieves high sensitivity and wide dynamic range with minimal distortion in the equalizer amplifier. The usual problems with inferiors signal-to-noise ratio in low-level preamplifier circuits have been solved by the use of PNP-type semiconductors in the first stage. The result is smooth, undistorted phono reproduction with nothing but total silence in the background.
For improved reliability and long-term stability, the entire EQ amp section has been incorporated in an integrated circuit.

Bipolar Power Supply
Amplifier power supplies are often a source of crosstalk and intermodulation distortion. The AS-M30 however, incorporates a bipolar power supply with a massive transformer and large 4,700 μF capacitors to assure maximum stability and minimum distortion even at the highest output levels. There's plenty of power to spare for the most dynamically challenging passages.

Unique Tone Control Configuration
The AS-M30 tone control circuitry is fully incorporated into the power amplifier negative feedback loop, eliminating the usual additional stage of amplification. This not only contributes to circuit economy, but also means extra low-distortion tone control.

41-Position Detent Volume Control
A large, easy-to-handle volume control knob permits accurate setting of listening levels with a minimum of fuss. Its 41 detent positions are ideal for reference level location, and they make it easy to reset desired volume levels.

Connections for Two Independent Tape Decks
Connect two reel-to-reel and a cassette deck for maximum recording flexibility. A tape copy switch is also provided; you can dub recordings from either deck to the other by simply flipping a switch. This eliminates the time-consuming fuss of Having to reconect tape deck leads every time you want to copy a tape.

Speaker Selector Switch
This important feature lets you use two sets of stereo speakers with convenient switching from the front panel. You can select set A, set B or sets A and B simultaneously. Set up all four speakers in one room for an „all-round” sound, or place one set in another room for an expanded listening environment.
The speaker selector switch also has an Off position which mutes both sets of speakers, but keeps the headphone jack active – convenient for late-night listening via headphons.

Loudness Control
At low listening levels, the sensitivity of the human ear to low high frequencies decreases. Music tends to lack presence and sound „dull”.
To compensate for this, the AS-M30 incorporates a loudness control which boosts the lows and highs in accordance with the ear's frequency loss curve.
This means that you hear all your music in the proper perspective even at low volume.
Continuous Reted Power: 30 W per channel (20-20,000 Hz, 8 ohms, no more than 0,1% THD, both channel driven)
Total Harmonic Distortion:
No more than 0,1% at rated power
No more than 0,05% at 1 W/1 kHz
Input Sensitivity/ Impedance:
Phono : 2,5 mV/47 k Ω
Tuner : 150 mV/47 k Ω
Tape 1, 2 : 150 mV/47 k Ω
Phono Maximum Input Level: 150 mV
Output Level/Impedance:
Tape 1, 2 : 150 mV/47 k Ω
Headphones : 8 Ω
Speaker : Off, A, B, A + B / 8 Ω or more
Frequency Response: 20 – 20,000 Hz +0 -1dB
Tone Control:
Bass : ±9 dB at 100 Hz
Treble : ±9 dB at 10 kHz
Loudness Control: -8 dB at 100 Hz; +4 dB at 10 kHz
Signal-to-Noise Ratio:
Phono : 70 dB
Tuner, Aux, Tape : 90 dB
Power Requirement: 100/117/220/240 V AC 50/60 Hz
Power Consumption: 115 W at rated power output (13W at no signal)
Dimensions (W x H x D): 410 x 145 x 290 mm (16-1/8” x 5-11/16” x 11-7/16”)
Weight: 7 kg (15 lbs 6 oz) Net

Teac AT-X30

 Teac AT-X30   
AM/FM Stereo Tuner
High-Sensitivity Front End, Dual Meters, FM Auto, PLL MPX Demodulator

High-Sensitivity TEAC Tuner with Clean-Styling Panel
inside and out, the Teac AT-X30 is extra-clean. Its simple panel design is backed by circuitry that assures clean reception of all AM and FM broadcasts. The AT-X30 is also packed with convenience extras like FM Auto stereo with built-in muting function and precise dual-meter tuning system.

Advanced Front End
At AT-X30 front end gives you clean, clear reception of even weak or distant stations. The circuitry, incorporating ll high-quality components, is perfectly balanced formaximum performance under the widest range of reception conditions. A smooth 3-gang tuning capacitor assures maximum frequency-calibration accuracy over the entire reception bandwidth for pinpoint tuning on all stations. The high-quality reception of this unit is further improved by the use of a 2-element ceramic filter in the IF stage.

Low-Distortion MPX Demodulator
A special Phase-Locked Loop (PLL) IC in the FM multiplex demodulator stgae assures ultra-low distortion and superb stereo separation. Providing 38 dB stereo separation, this section assures excellent imaging and clarity in the stereo field. In addition, since the most critical circuitry is incorporated in a single IC chip, greater operation stability and reliability has been achieved.

Three-Way Selector
this easy-grasp knob lets you choose AM or FM Auto for normal listening conditions. When an FM stereo signal is received, the AT-X30 automatically switches to Stereo reception. In particularly difficult reception situations, switching to the Mono position will eliminate most of the background noise from an FM signal. In the FM Auto position, a handy FM muting function is automatically engaged. This feature eliminates annoying inter-station noise while tuning.

Dual Tuning Meters
An outstanding feature for a tuner in this class, the AT-X30
's dual tuning meters let you find the best tuning spot for any station with pinpoint accuracy. The signal-strength of incoming signals; use it to tune both AM and FM stations. For precise FM station alignment, the center-tune meter needle reads dead center when the station is tuned meter needle reads dead center when the station is tuned so that stereo separation is optimum and distortion is minimum.

Other Features
Easy-view linear dial scale - longer for clearer station indication.
Convenient center-panel tuning knob.
High-inertia flywheel-type tuning knob for smooth, accurate tuning with no backlash.
FM Section
Tuning Range: 88 – 108 MHz
Usable Sensitivity: 10,8 dBf/1,9μV
Selectivity: 50 dB (400 kHz)
Image Response Ratio: 60 dB
IF Response Ratio: 70 dB
AM Suppression Ratio: 55 dB
Capture Ratio: 1,0 dB
Harmonic Distortion: 0.3% (Stereo 1 kHz)
Signal-to-Noise Ratio: 70 dB
Stereo Separation: 50 dB (1 kHz)
Frequency Response: 50 Hz – 15 kHz +0,5/-1,5 dB
Antenna Impedance: 300 Ω Balanced; 75 ohms Unbalanced
Output Level/Impedance: 600 mV/ 4,5 k Ω
AM Section
Tuning Range: 535 – 1,605 kHz
Usable Sensitivity: 300 μV/m
Selectivity: 30 dB
Image Response Ratio: 60 dB (1 kHz)
IF Response Ratio: 40 dB (1 kHz)
Output Level: 120 mV/4,5 k Ω
Power Requirements: 100/117/220/240 V AC, 50/60 Hz
Power Consumption: 12W
Dimensions (W x H x D): 410 x 145 x 300 mm (16-1/8” x 5-6/8” x 11-7/8”)
Weight: 5 kg (11 lbs)

Teac TS-F30

 Auto-Return / Auto-Cut Control
No longer do you have to drop whatever you’re doing and run to the turntable every time a record ends. With the TS-F30, the tonearm is returned to the rest at the end of every record, letting you change it when you’re ready. The auto-cut control allows you to stop the record during play, at which time the tonearm will automatically return. In addition, a smooth manual arm lifter is provided so you can gently lower the needle onto the record, or raise it and move it to another track.
Front-Panel Operation
Here's a feature you'd expect an engineering-oriented company like Teac to come up with: front-panel operation. Besides being convenient, this system helps protector your records and stylus from the platter shake caused by raising and lowering the dust cover while the needle is tracking a record. Only three knobs are required to handle all turntable functions, making the TS-F30 the ultimate in operating ease.
 Reliable Driver System
the TS-F30 incorporates 4-pole synchronous motor and 2-speed belt-drive system for optimum accuracy and stability of platter rotation at both turntable speeds. This system gives the TS-F30 an inaudible wow and flutter level of 0,09% (WRMS).
Sensitive S-Shaped Tonearm with Anti-Skating Control
the TS-F30's highly-sensitive static-balanced tonearm with built-in anti-skating mechanism tracks even warped records superbly. Tonearm balance is easily adjusted to match any cartridge, and the accuracy of the anti-skating control enhances record and stylus life and gives true stereo balance.
High Quality VM-Type Cartridge
the standard cartridge that comes with the TS-F30 is a high-quality VM-type from Audio Technica. The precision design of this cartridge assures that it will perform in the same way as the cutting head originally used to produce the record, providing optimum playback characteristics. Dual magnets arranged in a “V” configuration give you plenty of output for any preamplfier, and provide improved channel separation and accurate imaging.
Other Features
Adjustable tonearm counterweight (stylus pressure: 0 -4 g) - Non-resonant aluminum headshell – Tough hinged dust cover – Resonance-damping record mat – Elegant brushed aluminum control panel.
Drive System:  Belt-drive.
Motor:  4-pole Synchronous Motor.
Speeds:  33-1/3 and 45 rpm.
Platter:  301 mm diameter, aluminum.
Wow and Flutter:  0.09% WRMS.
Signal-to-Noise Ratio:  42 dB.
Cartridge Type:  VM-type.
Frequency Response:  20 – 20,000 Hz.
Output Voltage:  4 mV.
Stylus Pressure:  1,5 – 2,5 grams.
Stereo Channel Separation:  28 dB/1,000 Hz.
Load Impedance:  47 k Ω
Tonearm Type:  Static-balanced with anti-skating device.
Stylus Pressure Range:  0 – 4 grams.
Overhang:  15 mm.
Power Requirements:  110/117/220/240 V AC, 50/60 Hz.
Power Consumption:  10 W.
Dimensions (W x H x D):  452 x 147 x 400 mm, (17-7/8” x 5-3/4” x -3/4”).
Weight:  6,2 kg (13 lbs 11 oz) net.

Optonica SM-110H

 Optonica SM-110H
Integrated Stereo Amplifier with Zero Switching System
This high-efficiency zero-switching amp employsOptonica's advanced semiconductor technology and innovative spikeless amplifier design to eliminate switching distortion and ensure low thermal loss. With a zero-switching system controlling each output transistor, just enough current is provided to prevent cutoffs and the resulting distortion. The OCL/ICL (outputcapacitorless/input capacitorless) preamplifier stage with differential FET and DC servo control ensure the most accurate possible signal at all frequencies. The more than ample power rating of this unit is supplied without distortion, while innovative DC servo circuitry provides all the advantages of a DC amplifier and eliminates the adverse effects of output capacitors. The DC servo equalizer makes it unneccessary to employ a step-up transformer or head amplifier when using a moving-coil cartridge. A remote action switch has allowed the input and output connections to be placed as close as possible to pre-amplifier and power output stages to reduce noise generation at the input and speaker output connections. Rec Out selection is simplified and totally unafected by the position of the input selector. A full range of controls essential to tailoring the response of a stereo system are provided. The system is safeguarded by an automatic protection circuit.
 Zero-switching output circuitry and a spikless amplifier design combine to eliminate distortion caused by power stage cutoff while maintaining output efficiency.
 Straight DC servo circuitry eliminates all coupling elements, including output capacitors, to eliminate distortion.
 The DC servo equalizer makes it unneccessary to employ a step-up transformer or head amplifier when using a moving-coil cartridge.
 The MC/MM phono selector switch allow you to take advantage of either type of cartridge.
 Remote action switch suppresses noise generated at input and output connections.
 Separate Rec Out and input selectors allow extra recording and listening versatility.
 The full range of controls includes loudness, subsonic filter and mode switchess plus 11 click-stop bass and treble controls.
 The 4-position speaker selector provides a variety of listening arrangements with two speaker systems.
 The automatic protection circuit shuts off the output stage of the amplifier to prevent damage to the amp and speakers, and indicates circuit status with a 2-colour LED.
Power Amp Section
Circuitry: pure complementary OCL, ICL, High Gain DC amplifier
Continuous Power Output
At 1 kHz  (both channel driven, 0,01% distortion):
2 x 100 W at 4 Ω
2 x 70 W at 8 Ω
From 20 to 20,000 Hz (both channels driven 0,05% distortion):
2 x 85 W at 4 Ω
2 x 65 W at 8 Ω
Intermodulation Distortion:  0,01% at rated power
Power Bandwidth:  10 Hz - 50 kHz at 0,05% distortion, 8 Ω
Pre Amp Section
Equalizer:  OCL type DC amp., equalizer with first stage FET, differential ICL and DC servo circuit
Tone Control:  NF type,differential amplifier dual power supply
Input Sensitivity/Impedance:
Phono MM :  2,3 mV/47 k Ω
Phono MC :  0,23 mV/100 Ω
Aux :  150 mV/47 k Ω
Tuner :  150 mV/47 k Ω
Tape PB 1 and 2 :  150 mV/47 k Ω
Output Level/Impedance:
Rec 1 and 2 :  150 mV/47 k Ω
Rec (DIN socket) :  30 mV/82 k Ω
RIAA Curve Deviation:  ±0,3 dB (20 -20,000 Hz)
Allowable Maximum Input for Equalizer:
Phono MM :  130 mV (RMS, 1 kHz)
Phono MC :  13 mV(RMS, 1 kHz)
Frequency Response:  DC to 80 kHz +0 -2 dB
Signal-to-Noise Ratio (IHF A-Network, Input short circuited):
Phono MM :  83 dB
Phono MC :  63 dB
Aux, Tuner or Tape Pb :  103 dB
Tone Control:
Bass :  ±10 dB at 100 Hz
Treble :  ±10 dB at 10 kHz
Low Filter:  -3 dB at 30 Hz , 6 dB/oct
Loudness:  +6 dB at 100 Hz; -4 dB at 10 kHz
Semiconductors:  42 Transistors, 38 Diodes, 13 LEDs, 6 FETs, 3 Ics
Power Source:  110/220/240 V 50/60 Hz AC
Power Consumption:  500 W
Dimensions (W x H x D):  430 x 141 x 387 mm (16-15/16" x 5-9/16" x 15-1/4")
Weight:  10,7 kg 923,6 lbs)

Optonica RT-7070H/HB

 Optonica RT-7070H/HB
Double Recording /Playback Stereo Cassette Tape-Deck with Dual Dolby and APSS
To conquer the performance problems of conventional cassette deck, Optonica divided the functions of a deck into recording and playback systems and created the RT-7070H/HB. Two independent transport systems driven by separate FG servo DC motors are incorporated, each with its own compartment and amplifier. The separate transport used only for recording features a wide-gap Sendust-and Sendust recording head that provides high recording sensitivity, good linear response and wide dynamic range. The 2-stage direct-couped NPN/PNP amp for the recording section offers high saturation, extreme linearity and wide dynamic range. The playback section is equipped with an ultra-narrow-gap Sendust-and-Sendust playback head that results in an absolute minimum of gap signal loss while optimizing frequency response across the frequency range. This section has a 3-stage ICL amplifier with state-of-the-art FET circuitry that eliminates the need for distortion-causing coupling capacitors. Dubbing can be performed with none of the loss in quality usually associated with cables and hook-up jacks. Each compartment has its own Dolby Noise Reduction system.
The RT-7070H/HB is equipped with APSS for one-touch skipping or repetition of desired selections, a record-mute button for one-touch editing, a 4-position tape selector to provide the correct settings for metal, CrO₂, FeCr and normal tapes. Digital meters display accurate input levels and have a peak hold function.
 Transport for recording/erase and playback are driven by separate FG servo DC motors to ensure stable motor speed.
Since each section performs only its assigned functions, the tape-heads could be aligned with the transport system for optimum tape alignment.
A wide-gap Sendust-and-Sendust head to assure high recording sensitivity is used for recording, while a double-gap head is provided for erasing to guarantee clean response.
For the playback section, an ultra-narrow-gap Sendust-and-Sendust head keeps gap signal loss to a minimum and optimizes frequency response.
The two perfectly matched tape compartments allow high quality dubbing for Tape 1 to Tape 2, while the three-mode level control function facilitates dubbing.
Dolby Noise Reduction vircuitry is provided for each tape compartment to reduce tape hiss. 
The MPX filter can be used to ensure optimum FM Dolby recordings.
APSS permits playback of desired selections at the touch of a button.
Metal tape capability allows you to makes use of the greatly extended frequency response, increased dynamic range and lower distortion of metal tapes.
Mechanical Section
Capstan Drive : FG servo DC-motor (Tape 1)
Reel Drive : FG servo DC-motor (Tape 2)
Record/Playback : Narrow-gap Sendust head (for playback - Tape 1)
Erase : Double-gap Ferrite head (for erese – Tape 2)
Others : Wide-gap Sendust head (for recording & monitor)
Wow and Flutter:
DIN (45 500) : ±0,15%
WRMS : ±1,0%
Tape Speed Deviation: ±1,0%
FF/RW Time: 110 sec (C-60)
Audio Section
Frequency Response:
Normal Position : 20 – 16,000 Hz (DIN 45 500); 30- 16,000 Hz ±3 dB
CrO₂ Position : 20 – 18,000 Hz (DIN 45 500); 30 – 18,000 Hz ±3 dB
Fe-Cr Position : 20 – 19,000 Hz (DIN 45 500), 30 – 19,000 Hz ±3 dB
Metal Position : 20 – 20,000 Hz (DIN 45 500), 30 – 20,000 Hz ±3 dB
Signal-to-Noise Ratio (Fe-Cr Tape):
Dolby NR Off : 57 dB
Dolby NR On : 67 dB at over 5 kHz
Recording Sytem: AC bias (105 kHz)
Erase System: AC erase (105 kHz)
Input Sensitivity/Impedance:
Line -In : 50 mV/50 k Ω
Rec/Pb (DIN) : 1 mV/ k Ω
Output Level/Impedance:
Line-Out : 1,000 mV/50 k Ω at 0 dB
Rec/Pb (DIN) : 1,000 mV/50 k Ω  at 0 dB
Headphones : 125 mV/ 8 Ω   at 0 dB
Power Source: 110/220/240 V 50/60 Hz AC
Power Consumption: 20 W (220 V)
Dimensions (W x H x D): 430 x 114 x 321 mm
Weight: 7,5 kg
Colour Front Panel:
Silver : RT-7070H
Brown : RT-7070HB

Toshiba SB-A50

 Toshiba Aurex SB-A50 Stereo Integrated Amplifier (1980)
Continuous Power Output
(20 Hz - 20 kHz both channel driven):
2 x 35 W at 4 Ω
2 x 30 W at 8 Ω
(1 kHz both channel driven):
2 x 38 W at 4 Ω
2 x 35 W at 8 Ω
Total Harmonic Distortion:  0,1% at rated power 8 Ω
Frequency Response:  5 Hz - 100 kHz  +0 -3 dB
Power Bandwidth (IHF):  10 Hz - 35 kHz
Load Impedance:  4 - 16 ohms
Damping Factor:  25
Signal-to-Noise Ratio (IHF A Network):
Phono :  70 dB
Tuner :  90 dB
Aux :  90 dB
Input Sensitivity/Impedance:
Phono :  2,5 mV/47 k Ω
Tuner :  150 mV/47 k Ω
Aux/Tape :  150 mV/47 k Ω
Mic :  1,0 mV/47 k Ω
Output Level:
Tape Rec :  150 mV
Tone Control:
Bass :  ±8 dB at 100 Hz
Treble :  ±8 dB at 10 kHz
Phono Overload Level:  150 mV (RMS)
Power Supply:  220V 50 Hz (for Europe)
Power Consumption:  290 W
Dimensions (W x H x D):  420 x 116 x 286 mm
Weight:  5,4 kg

Philips GA 212

 Philips GA212
That Philips make Hi-Fi of the highest quality as well as good domestic audio equipment is most clearly demonstrated by the new GA212 „electronic” record deck.
This shows technological innovation of a high order, resulting in genuinely better standards of record reproduction.
Its two speeds (33-1/3, 45 rpm) can be adjusted precisely, using the built-in stroboscopic rings and fine-speed controls, and are accurately maintained by a tacho generator that keeps wow and flutter to less than 0,1%. 
 Speed selection is by „skin-sensitive” controls that light-up when touched.
Floating suspensions of the turntable and pick-up arm gives excellent insulation against shocks and vibration, resulting in very low rumble and very accurate cueing.
Turntable and pick-up arm have been mounted on a sub-chassis which is suspended from the rigidly mounted main chassis. Considerably more flexible springs can therefore be used. And as the motor is independently mounted underneath the main chassis, the pick-up arm is doubly insultated against vibrations from the motor.
the tracking error of the virtually frictionless low-resonance pick-up arm is exceptionally low. Side-thrust may be compensated at all playing weights for both conical and elliptical styli.
The Philips slide-in carrier accepts virtually any pick-up cartridge with fixing centres to the 1/2” international standard. A Philips GP400 Super M magneto-dynamic cartridge is supplied.
 Switching on and off is done silently through a bi-stable multi-vibrator, operated by relay-type switches.
Autostop at the end of a record is not effected by mechanical means, but electronically. When the rate of interception of a ligh-beam striking a photo-sensitive cadmium sulphide cell exceeds a certain value, a bi-stable multivibrator is triggered, cutting off the motor supply voltage. Hence „thumping” and groove jumping cannot occur. The pick-up can be lowered precisely into any groove, even close to the run-out, without premature switch-off.
Drive System:  belt drive
Speed Control:  electronic
Speeds:  33  and 45rpm
Speed Adjustment Range:  ± 3%
Wow and Flutter:  0.1%
Rumble (DIN B):  62 dB
Arm Friction: 15 mgf
Stylus Force:  0.75 to 4g
Line Voltage:  110/120 V, 220/240 V; 50/60 Hz
Power Consumption:  5 W (at 120 V)
Dimensions (W x H x D):  390 x 150 x 330 mm
Weight:  6 kg

Pioneer SA-7500

 Pioneer belives in music. And when a Pioneer product like the SA-7500 integrated stereo pre/main amplifier reaches the production stage after months of refinement, you can be sure it stresses musicality above all else. Handling creative musical information requires as much or more precision as is needed in today's  most sophisticated measuring apparatus and communications systems. This is why Pioneer is not siply an expert in modern electronics but a respected high fidelity audio specialist as well.
The SA-7500 bears this out. It has all the latest circuits and facilities, including a precision phono equalizer and extra-versatile tone control section. And it has a higher power rating than most pre-main models in its class. Continuous power output of 40 watts per channel, min. RMS at 8 ohms from 20 Hz to 20 kHz with no  more than 0,3% total harmonic distortion. Yet feature for feature, it's priced less than most of the competition. 
Power Amplifier - The SA-7500 employs high reliability NPN and PNP silicon power transistors. Together with the differential first stage, all stages are direct coupled in a pure complementary OCL circuit configuration. Careful circuit design and selection of components results in a wide output bandwidth.

Precision Tone Control Functions -  Conventional Bass and Treble controls are each provided with Turn Over switches for selecting the frequencies at which the controls take effect. A convenient Tone switch is also included which permits a flat frequency response to be obtained regardless of the tone control settings.
Close RIAA Equalization - RIAA deviation, which governs record playback fidelity, is reduced to very close tolerance by strinently selected equalizer elements. A dual DC power supply system is also employed to provide increased acceptable input volume, resulting in expanded dynamic range and faithful record performance at low distortion.

Protection Circuit - Electronic circuitryand a relay are combined in a fast action protection circuit which guards transistors and speakers from damage in the event of defective connections, such as speaker terminal shorting. When DC current appears in the output, the output circuit is instantly opened. The protection circuit also performs a muting function when the power switch is operated.
Power Amplifier Section
Circuitry:  1-stage differential amplifiers - Direct coupled OCL
Power Output (20 - 20,000 Hz with no more tha 0,3%THD):
40 watts per channel min. RMS at 8 Ω
45 watts per channel at 4 Ω
Continuous Power Output (at 1,000 Hz Both channel driven):
45 watts per channel at 8 Ω
50 watts per channel at 4 Ω
Total Harmonic Distortion (at 20 Hz - 20,000 Hz):
Continuous Rated Power Output :  no more than 0,3%
20 watts per channel Power Output, 8 Ω :  no more than 0,05%
1 watt per channel Power Output, 8 Ω :  no more than 0,05%
Intermodulation Distortion (at 20 Hz - 20,000 Hz ):
Continuous Rated Power Output :  no more than 0,3%
20 watts per channel Power Output, 8 Ω :  no more than 0,05%
1 watt per channel Power Output, 8 Ω :  no more than 0,05%
Frequency Response:  10 Hz to 80,000 Hz  +0 -1 dB
Input Sensitivity/Impedance
Power Amp In :  1 V/50 k Ω
Speaker :  A, B, A + B
Headphone : Low impedance
Damping Factor (20 Hz - 20,000 Hz, 8 Ω):  25
Hum and Noise (IHF, Short-circuited A Network):  100 dB
Preamplifier Section
Equalizer Amplifier :  3-stage direct-coupled amplifier
Control Amplifier : 2-stage direct-coupled with 1 FET NFB type
Input Sensitivity/Impedance:
Phono 1 :  2,5 mV/50 k Ω
Phono 2 :  2,5 mV/50 k Ω
Mic "  7,5 mV/85 k Ω
Tuner :  150 mV/50 k Ω
Aux :  150 mV/50 k Ω
Tape PB 1 :  150 mV/50 k Ω
Tape PB 2 (DIN connector) :  150 mV/50 k Ω
Phono Overload level (THD 0,1%)
Phono 1 :  200 mV (1,000 Hz)
Phono 2 :  200 mV (1,000 Hz)
Output Level Impedance:
Tape rec 1 :  150 mV
Tape rec 2 (DIN connector) :  30 mV/80 k Ω
Pre Out :  1 V/1 k Ω
Total harmonic Distortion (at 20 Hz - 20,000 Hz):  no more tha 0,05%
Frequency response:
Phono (RIAA standard):  30 Hz - 15,000 Hz ±0,3 dB
Tuner, Aux, Tape PB :  10 Hz - 50,000 Hz +0 -1 dB
Tone Control
Bass :  ±7 dB (100 Hz)/ ±11 dB (100 Hz); Turnover Frequency 200 Hz / 400 Hz
Treble :  ±7 dB (10 kHz)/ ±11 dB (10 kHz), Turnover Frequency 5 kHz / 2,5 kHz
Low :  30 Hz (6 dB/oct)
High :  8 kHz 96 dB/oct)
Loudness Contour (volume control set at -40 position):
+8,5 dB at 100 Hz
+4 dB at 10 kHz
Hum and Noise (IHF, Short-circuited, A Network):
Phono 1, 2 :  70 dB
Mic : 65 dB
Tuner, Aux, Tape PB :  90 dB
Muting:  0, -20 dB
FETs :  2
Transistors :  35
Diodes :  21
Power Requirements:  110 -120 V / 220 -240 V 50/60 Hz
Power Consumption:  200 watts (at 110-120 v AC)
Dimensions (W x H x D):  420 x 150 x 345 mm (16-9/16' x 5-7/8" x 13-9/16")

Weight (net):  12 kg (26 lb, 7 oz)

Pioneer SA-800

 The Pioneer SA-800 is a professional stereo amplifier that, in performance and specifications, ranks with the very finest of high power units now being manufactured taday. It has a multitude of features that make it suitable for most anyone's home stereo system, but especially one that requires multiple-purpose versatility.
The SA-800 employs all-stage direct coupling circuitry in the power amplifier section, a vast improvement over conventional circuitry using coupling capacitors, and the result is an astonishingly wide power bandwidth of 5 - 50,000 Hz (at 8 ohms).
The unit also has a high-grade protector circuit using relays and transistor which safeguards the speakers and output transistors under all conditions.
There are two sets of tape terminals for easy tape-to-tape duplicating; there are also dual phono terminals which can accommodate both moving magnet and moving coil cartridge turntables. There are other extras, too, which make the SA-800 a truly professional instrument as well as tremendous investment in the kind of quality that Pioneer continues to make famous.
Power Amplifier Section
Music Power Output (IHF):  165 watts at 4 ohms; 108 watts at 8 ohms
Continuous Power Output (each channel driven): 
53 watts / 53 watts at 4 ohms
41 watts / 41 watts at 8 ohms
Continuous Power Output (both channel driven):
39 watts + 39 watts at 4 ohms
34 watts + 34 watts at 8 ohms
Power Output in the range of 20 to 20,000 Hz (both channel driven):
26 watts + 26 watts (8 ohms, harmonic distortion less than 0,5%)
Total Harmonic Distortion:  less than 0,5%
Intermodulation Distortion:  less than 0,5%
Power Bandwidth (IHF):  5 to 50,000 Hz (8 Ω, THD less than 0,5%)
Frequency Response:  5 to 80,000 Hz ±1 dB
Input Sensitivity/Impedance:  560 mV/100 k Ω (1 kHz continuous power output)
Speakers:  4 to 16 Ω
Damping Factor:  65 (8 Ω, 1 kHz)
Center Channel Output :  500 mV
Preamplifier Section
Output Voltage:  3 V (rated output); 5 V (max.)
Harmonic Distortion:  less than 0,1%
Frequency Response:  20 to 60,000 Hz ±1 dB
Input Sensitivity/Impendance:
Phono 1 (Mag) :  3 mV/50 k Ω
Phono 1 (Cer) :  56 mV/100 k Ω
Phono 2 (MM):  3 mV/50 k Ω
Phono 2 (MC):  110 µV/30 Ω
(with phono input transformer model PP-402)
Mic :  2,3 mV/25 k Ω
Tuner :  230 mV/200 k Ω
Aux 1, 2 :  230 mV/200 k Ω
Tape Monitor 1, 2 :  230 mV/200 k Ω
Recording Output:
Tape Rec 1, 2 (Pin Jack) :  230 mv
Tape rec (DIN) :  35 mV
Tone Control:
Bass :  -9 dB, +12 dB at 100 Hz (3 dB step)
Treble :  -12 dB, +9 dB at 10 kHz (3 dB step)
Low Filter :  -3,5 dB/ 60 Hz (12 dB/oct)
High Filter :  -3 dB/6 kHz (12 dB/oct)
Equalization Curve:  Phono - RIAA standard
Loudness Contour:  +11,5 dB/100 Hz ; +6 dB/10 kHz, with volume control set at -40 dB position
Muting:  -20 dB
Hum and Noise(IHF): 
Phono :  more than 80 dB
Tuner, Aux :  more than 100 dB
Channel Separation (1 kHz):
Phono :  more than 50 dB
Tuner, Aux :  more than 55 dB
Power Requirement:  110, 120, 130, 220, 240 V (switchable)  50/60 kHz
Power Consumption:  230 watts (max.)
Dimensions (W x H x D):  430 x 145 x 337 mm (16-15/16" x 5-11/16" x 13-1/4")
Weight:  10,3 kg (23 lb) net

Quad FM4

 At the touch of button the Quad FM4 gives access to a variety, breadth and quality of programme material that the most dedicated gramophile would find difficult to equal. Indeed the emotional satisfaction which can be gained froma well engineered live broadcast is second only to being at the concert itself. A FM tuner is thus an essential piece of equipment for any serious listener to music. The FM4, as one might expect from Quad is deceptively simple and original. Good ergonomics and advanced electronics are combined to procedure a tuner with exceptional audio performance and ease of handling.

The Quad FM4 is designed as an adjunct to a high quality music system.  As such emphasis in design is placed upon obtaining audio performance from a reasonable input signal rather than the ultimate in selectivity.  Performance of the Fm4 is such that given adequate signal strength,  it makes no audible contribution to the incoming programme, and provides absolutely faithful reproduction of the original transmission.

The only controls on the FM4 are an on/off switch, tuning knob and eight pushbuttons which are used to store and recall stations in the tuner's memory. The tuned frequency is shown in figures and an ingenious bar graph display provides simultaneous information of signal strength and centre tuning. A specially developed dedicated imcroprocessor makes all decisions about muting and AFC and also controls the tuner's memory in which are stored the  preset stations.
 Operating the Quad FM4 issimplicity itself. Once programmed it is only necessary to press one of the seven preset buttons for the wanted station to be tuned in perfectly.
Programming stations into the tuner's memory is very straightforward. The desired frequency is located by rotating the tuning knob, which will have conspicuous advantages for anybody who has tried to find a station using pushbuttons to track up and down. The bar graph confirms that the station is correctly tuned and being received with sufficient signal strength to give acceptable signal to noise.
AFC and muting is taken care of automatically. Stereo over-ride, required if the signal is very weak, is achieved by switching the Quad 44 to MON and adjusting the balance control for minimum noise.
Programmes will remain stored in the tuner 's memory almost indefinitely provided that the tuner is used once in a awhile, and for up to five years even if it is disconnected from the mains.
When switched on the tuner remembers the station last used and automatically reverts to it.
Frequency Range:  88 - 108 MHz
-30  dB Quieting  [mono] :  1 µV 
50 dB Quieting [mono/stereo] :  2,7 µV / 25 µV
Full Limiting:  less than 1 µV
Signal-to-Noise Ratio (Input signal 1 kHz at 1 mV, A weighted):
Mono :  76 dB
Stereo :  70 dB
Distortion Input Signal (1 kHz):
±75 kHz [mono/stsreo] :  0-15%/0-15%
±25 kHz [mono/stsreo] :  0-05%/0-10%
Selectivity:  53 dB
Capture Ratio: 2-5 dB
IF Rejection:  100 dB
AM Suppression:  60 dB
Image Rejection:  80 dB
Pilot Tone Suppression:  60 dB
Crosstalk at 1 kHz:  40 dB
Frequency Response:  20 - 15 kHz :  +0 -1 dB
Output Level 30 % Modulation:  100 mV recommended load Impedance
Source Indepedance:  100 Ω
Recommended Load Impedance:  more than 20 k Ω
Aerial Input:  75 Ω unbalanced
De-emphasis:  50 µSec or 75 µsec)
Power Input:  100-125 or 200-250 50/60 Hz  6VA
Dimensions:  (W x H x D):  321 x 64 x 207 mm
Weight:  3 kg